ABB RELION 670 Series Technical Manual page 1036

Section 16
Monitoring
16.1.7 Operation principle
16.1.7.1 Measurement supervision
The protection, control, and monitoring IEDs have functionality to measure and further process
information for currents and voltages obtained from the pre-processing blocks. The number of
processed alternate measuring quantities depends on the type of IED and built-in options.
The information on measured quantities is available for the user at different locations:
• Locally by means of the local HMI
• Remotely using the monitoring tool within PCM600 or over the station bus
• Internally by connecting the analog output signals to the Disturbance Report function
Phase angle reference
All phase angles are presented in relation to a defined reference channel. The General setting
parameter
Zero point clamping
Measured value below zero point clamping limit is forced to zero. This allows the noise in the input
signal to be ignored. The zero point clamping limit is a general setting (
P, Q, PF, V, I, F, IA, IB, IC, VA, VB, VC, VAB, VBC, VCA, I1, I2, 3I0, V1, V2 or 3V0). Observe that this
measurement supervision zero point clamping might be overridden by the zero point clamping
used for the measurement values within CVMMXN.
Continuous monitoring of the measured quantity
Users can continuously monitor the measured quantity available in the function block by means of
four defined operating thresholds, see figure 535. The monitoring has two different modes of
operating:
• Overfunction, when the measured current exceeds the High limit (
XHiHiLim ) pre-set values
(
• Underfunction, when the measured current decreases under the Low limit (
low limit (
X_RANGE is illustrated in figure 535.
1030
PhaseAngleRef defines the reference.
XLowLowLim ) pre-set values.
1MRK 502 066-UUS B
SEMOD54417-130 v3
SEMOD54417-303 v5
SEMOD54417-137 v4
XZeroDb where X equals S,
SEMOD54417-140 v4
XHiLim ) or High-high limit
XLowLim ) or Low-
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